Now, an all-new take on the idea of a crash pad. Kids looking for a place to party, and finding it in the real estate listings. Here's Debra Roberts. Reporter: If you're in the market for 9,000 square feet of pure excess, we've found your new digs. Tucked in the hills of southern California, this lavish mansion is one-of-a-kind. Unless you happen to know of another spread with medieval guards in the entryway and a casino down below. Add to that, five beds, nine baths, and a backyard that rivals the playboy mansion. Asking price, $12 million. This is a world-class property. You don't see these kind of places very often. Reporter: You've got secret entrances all over. Can you imagine, you know, you just touch it and it just opens. Reporter: It's an over-the-top fantasy dreamed up by homeowner nick radoee, who made a fortune in the trucking business and has money to burn. Who else would have a swimming pool that actually lights on fire? You can go under that slide and go through the fire and the water. Reporter: You really can? You're kidding! Nick may live in la habra heights, but his house parties are more Hefner than la habra. The Romanian party boy is often surrounded by scantily clad women. But the craziest party ever held here is one he never even attended because nick was out of the country. It's an infamous evening, that all starts with some teens and some tweets. Days before the actual party there was tweets going back and forth as to where this party was going to be. Detective Josue Rodriguez of the L.A. County sheriff's office says the luxury home was targeted after it was listed online. That they go on real estate sites, they see which homes are for sale, if it looks like it's vacant. They'll stage a party and invite a bunch of people. Reporter: So after casing the place, the teens decided to seize the moment. The party is a go. Party on. Party on. Reporter: The partiers get lucky. Turns out the security system isn't on. Big mistake. Make sure you have an up to date security system and most importantly, make sure that your broker is using it. Reporter: And neighbors don't report the noise, assuming it's coming from radoi's latest soiree. How many kids would you guess ultimately wound up at this party? The estimates that we have is somewhere between 150 to 200. Reporter: The turnout is mostly 15 to 18 year Olds. None serious buyers, but many serious drinkers. The outdoor refrigerators are raided as the kids treat themselves to wine, beer and champagne, says realtor David Wright. Everything liquid was gone. Reporter: Well into the evening, girls mug for the camera like it's a red carpet event. Guys party like rock stars into the wee hours. But when the alcohol runs dry from the outdoor bars, a window is jimmied, and the mob moves indoors. There was just no respect for the property, no respect for anything. Reporter: The sentries standing guard couldn't keep this crowd from storming this castle. In true medieval warfare, it was off with his head. Downstairs, another violent act is unfolding. We're probably about nine or ten feet below the surface of the water right here. Reporter: They shattered the window? Yeah, they shattered the window. If the water had come through, we estimate that it would probably would have killed him. There's 300,000 gallons of water here. Reporter: Sometimes, homeowners have no idea what's going on. Sometimes they do. The owners of this under-construction dream mansion in Ontario told CTV they actually gave permission for their son to hold a party here. In the understatement of the century, the teen told his parents he was having a few friends over. Those few turned into 1,500 bffs once the party was touted on social media. There was just kids coming in all way from down there. Packs of 10, 20. Literally no room to walk in the house. Reporter: Inside this 5,000-square-foot mega mansion, party-goers trashed the bash resulting in $70,000 in damages. There was a potential, a real potential for something to happen, something deadly. Reporter: Fortunately, that didn't happen. Meantime, back in la habra heights, nick radoi gets the cold hard facts. And the bill. On damage -- on this house, it was over a million. A million dollars of damage. Yes. The utter destruction, there was no reason for it. Reporter: It is now up to detective Rodriguez to solve the crime. And fortunately, the hapless high-schoolers leave so many clues, it won't be very difficult. The brazen mob not only partied all night, they tweeted all night, placing themselves at the scene of the crime. Boasting in their tweets, "The mansion party was fun but that house is blanked up to the max now," says one. "I swear everyone stole something from that house," says another. And they actually took pictures that night of themselves on the property? On the property. In the backyard. In the front yard. Inside the restroom. Reporter: Detectives made a point of arresting the teen suspects during school. What began as a house party is a million dollar crime. It's one of the most serious juvenile and adult crimes that we've come across. Reporter: 14 kids were arrested with charges ranging from trespassing to felony burglary. But happily for radoi, investigators recovered some of his unusual treasures, like this exotic stuffed snow leopard worth an estimated quarter million dollars. But other items may be gone for good. Much like radoi's peace of mind. You always felt so secure here. After this happened, you know, you don't feel the same anymore. You feel unsecure. Reporter: Did they sort of hang themselves through social media? They absolutely did. It helped them set up the party and it also helped us bring them

This transcript has been automatically generated and may not be 100% accurate.

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{"id":24533405,"title":"Mansions on Sale Targeted for Teen Bashes","duration":"6:11","description":"Teens go online, look for high-end properties on sale, and use the homes to party the night away.","url":"/2020/video/mansions-sale-targeted-teen-bashes-24533405","section":"2020","mediaType":"default"}